Prediction of Equivalency Factors for Various Subbase and Base Courses

The generation of waste materials from industries like iron, steel, coal, and so on is so large that all countries are facing a shortage of dumping space for these waste materials and it is also causing serious environmental pollution. There is also a huge shortage of aggregate material. With a view to save the costly aggregates and preserve the environment, it is desirable that local natural materials and industrial wastes are used to the maximum extent. This will also lead to economy. Being bound, these materials produce lesser pollution as compared with the freely dumped state. For example, fly ash, if carried away in the air, is most harmful when inhaled. However, concrete mixes are confined enough to cause pollution. In the research reported in this paper, the equivalency factors for various materials used in subbase and base courses have been evaluated experimentally. Subbase courses made of coarse sand, stone dust, riverbed material, blast furnace slag, and Linz-Donawitz slag have been studied with respect to granular subbase course. For the base course study, various stabilized mixtures and different combinations of wet-mix macadam have been studied with respect to wet-mix macadam mixed with 5% soil. This has been done to find out whether the use of these materials can be significant in pavement construction and, if so, then to what extent. The research reported in this paper has been done with respect to various properties like modulus of elasticity, resilient strain, permanent strain, compressive strength, shear strength, failure load, and so on.